Consider the following statement, which is intended to create an ArrayList named a to store only elements of type Thing. Assume that the Thing class has been properly defined and includes a no-parameter constructor.
ArrayList a = /* missing code /;
Which of the following can be used to replace / missing code / so that the statement works as intended?
A: new Thing()
B: new ArrayList()
C: new ArrayList(Thing)
D: new ArrayList()
E: new ArrayList<>(Thing)
Consider the following statement, which is intended to create an ArrayList named numbers that can be used to store Integer values.
ArrayList numbers = / missing code /;
Which of the following can be used to replace / missing code */ so that the statement works as intended?
new ArrayList()
new ArrayList
new ArrayList()
A: III only
B: I and II only
C: I and III only
D:II and III only
E: I, II, and III

When dealing with Java syntax you always need to initialize an ArrayList object with its constructor. From the options listed the only correct option would be B: new ArrayList(). This would correctly initialize the ArrayList object but is not necessarily the recommended way of doing this. The truly recommended way would be the following

ArrayList<Thing> a = new ArrayList<Thing>()

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MrRoyal MrRoyal · Answer 2 · 2022-01-07T16:51:54+01:00

ArrayLists are simply resizable array.

The statement that can replace the missing code is (b) new ArrayList();
The statements that can replace the missing code is (c) I and III only

The syntax to create an ArrayList is:

ArrayList<Type> str = new ArrayList<Type>();

Another possible syntax is:

ArrayList var_name= new ArrayList();

The above declarations mean that: the statement that can replace the missing code is (b) new ArrayList();

While the statements that can replace the missing code is (c) I and III only